Gene therapy vectors based on adeno-associated virus (AAV) serotype 2 have emerged as being preferred for achieving stable transduction following in vivo administration. However, while stability of transgene expression was impressive, its efficiency often was not.
Basic research and commercial development of vectors based on serotype 2 has been enhanced with the development of chromatographic methods for purification. With the development of other AAV serotype vectors has flowed the need for methods of purification of such vectors. One such vector, AAV serotype 5 (AAV5) has emerged as a useful vector. To date, however, purification of AAV5 based vectors required cesium chloride (CsCl2) sedimentation, since it does not bind heparin which has been used for purification of AAV2. CsCl2 sedimentation is time consuming, not scalable, and yields preparations that are heavily contaminated with cellular proteins.
What are needed are methods of purification for AAV5-based vectors which are rapid and may be readily scaled-up for use in production.